Table 3.

Suggested hypotheses for adaptive function in dorsal black‐brown coloration in male pied flycatchers

Adaptive function	Hypothesis		Suggested by	Support for the hypothesis	No support for or against the hypothesis
Strategies to cope with biotic and abiotic environments	Temperature	Color types are adaptations to different temperatures	Ilyina and Ivankina (2001)	Ilyina and Ivankina (2001), Sirkiä et al. (2010), Järvistö (2015)
	Humidity	Color types are adaptations to different amounts of precipitation	Sirkiä et al. (2010)	Sirkiä et al. (2010)
	Habitat	Color types are adaptations to different habitats	Ivankina et al. (1995)	Ivankina et al. (1995)	Belskii and Lyakhov (2004)
	Predation	Unprofitable prey: conspicuous males avoided by prey	Røskaft et al. (1986)	Götmark (1992, 1993, 1995), Post and Götmark (2006)	Slagsvold et al. (1995)
		Conspicuous prey more easily discovered by prey	Von Haartman (1985)	Slagsvold et al. (1995)	Götmark (1992, 1993, 1995), Post and Götmark (2006)
	Parasitism	Color types are adaptations to differences in parasitism	Dale et al. (1999)		Dale et al. (1999)
Signaling function in communication with conspecifics	Dominance signaling	Delayed plumage maturation	Slagsvold and Lifjeld (1988)		Curio (1959), Alatalo et al. (1982), Harvey et al. (1985), Slagsvold and Lifjeld (1988)
		Conspecific female mimicry	Slagsvold and Lifjeld (1988)	Sætre et al. (1993), Saetre and Slagsvold (1996)	Slagsvold and Lifjeld (1988), Lundberg and Alatalo (1992), Calhim et al. (2014)
		Signaling of presence	Slagsvold and Lifjeld (1988)	Dale and Slagsvold (1996)	Huhta and Alatalo (1993)
		Status signaling	Slagsvold and Lifjeld (1988)	Järvi et al. (1987), Slagsvold and Lifjeld (1988), Slagsvold and Sætre (1991)	Breiehagen and Saetre (1992), Huhta and Alatalo (1993)
	Coloration is signaling male quality to females	Black males have higher pairing/breeding success than brown males (in all contexts)	Røskaft and Järvi (1983)	Røskaft and Järvi (1983), Von Haartman (1985), Järvi et al. (1987), Sætre et al. (1994, 1995), Dale and Slagsvold (1996), Lifjeld et al. (1997), Gálvan and Moreno (2009), Canal et al. (2011)	Røskaft and Järvi (1983), Alatalo et al. (1984), Alatalo et al. (1986), Alatalo et al. (1990), Alatalo et al. (1994), Dale and Slagsvold (1990), Slagsvold (1986), Slagsvold and Lifjeld (1988), Lifjeld and Slagsvold (1988), Potti and Montalvo (1991a), Lundberg and Alatalo (1992), Kerimov et al. (1994), Rätti et al. (1995), Sætre et al. (1997), Slagsvold and Drevon (1999), Ivankina et al. (2001), Lehtonen, Primmer, et al. (2009), Gálvan and Moreno (2009), Sirkiä and Laaksonen (2009), Sirkiä et al. (2010), Moreno et al. (2010), Moreno, Velando, et al. (2013), Järvistö (2015)
Signaling function in communication with heterospecifics	Avoidance of hybridization	Avoiding hybridization with female collared flycatchers	Røskaft et al. (1986)	Sætre et al. (1993); Sætre et al. (1997), Veen et al. (2010)	Vallin et al. (2012)
	Heterospecific female mimicry	Avoiding competition with male collared flycatchers	Røskaft et al. (1986)	Král et al. (1988), Vallin et al. (2012)